package lianxi;

public class Suitang2 {
    public static void main(String[] args) {
        StringBuilder s = new StringBuilder("大家好!");
        s.append("我是程序员!");
        System.out.println(s);
        s.insert(6, "优秀的");
        System.out.println(s);
        s.replace(6, 9, "牛牛的");
        System.out.println(s);
        s.delete(0, 4);
        System.out.println(s);
    }
}
